Pneumatic flotation apparatus



Cet.. 5 1926.l

' O. H. JOHNSON PNEUMATIC FLOTATION APPARATUS Filed DSG; 17, 1923 V 2 Sheets-Sheet l m. Lw

M al@ my @m0/7.-

O. H. JOHNSON PNEUMATIC FLOTATION PPARATUS Oct. 5v 1926.

2 heets-Sheet Filed Dec. 17. 192';

' having a narrow elongated slot controlled Patented @et 5, 1926.

unirsi) STATES isolata PATENT `orifice.

OSCAR H. JOHNSON, F DENVER, COLORADO,

lrmaritrarre FLoTA'rIoN Armenians.

' Yapplicanm mea December 17, 192i. serial No. 523,166.

The object of this invention is to provide a pneumatic flotation machine -wherein the air may be introduced efciently'by simple.

pulp'and the pulp is drawn through a narrow opening' located between the aerating member and the bottom whereby it is thoroughly aerat-ed as it passes the aerating member and `contacts with the air stream.- The aerating member is in the form of an elongated nozzle by an adjustable strip or gate. y

In the drawings: I Figure 1 is a vertical cross'sectiony through a machine equipped with my invention;

F ig. 2 is a fragmentary plan view thereof.; Fig. 3 is a section taken on the line 3 3 of Fig. 1; A

Fig. 4 is a vertical cross section through the aerating'nozzle;

F ig. 5 is an eleva-tion showing theV aerat# ing member in the form of separate sections; "and Fig. 6 is a detail of va modified nozzle mounting.

The flotation tank may be composed of side. and end walls 10 and equipped with a froth overflow 12, a bottom wall 14 being provided for support of curved bottoms whose adjacent linner edges form a joint 16. The aerating device is in the form of a nozzle 18 which is disposed at such an acute angle to the vertical as will give efficient aeration and circulation. This angle may be at various points between the vertical and the horizontal according to conditions, that shown approximating 453. The nozzles are preferably arranged in pairs as shownabeing supported on the lower ends of partltioning walls 20 which divide the tank lnto an ascending column A and two descending columns D. 'Each nozzle member extends longitudinally of the cell and may be'either in the form of a single unit as in F ig. 3, or,

preferably, in the form of separate sections y alinedlongitudinally as in'Fig. 5.

The nozzles 18 are connected to the walls 2Q by means of upper castings 22 which are directly secured to the walls 20 by means of ears `24, the castings 22 being provided with threaded opemngs 25 for the reception of Y air conducting pipes 26 which extend downward along the walls 20 and are secured thereto by means of U-bolts 28. The upper castings or heads22 are secured to the nozzles 18 by means of ears 30 and' 32 with which the parts are provided respectively, and bolts 34. Where the nozzle is in the form of a single unit as in Fig. 3` a plurality of pipes 26 may be used therewith.' In the form of Fig. 5, each section will be apertured at 25 and be provided with its respective pipe 26. The inner wall of each nozzle is provided at its lower end with a boss 118 to which an adjustable gate is secured by screws 36 Opassing through short slots 38 in the gate. By loosening the screws 36 the gate 35 may be easily adj usted to produce the desired slot or opening at .the tip of the nozzle and thereby control the introduction of air therefrom.'

The walls 20 are themselves bodily'adj usted to vary the space between the bottoms 15 and the nozzles 1 8, and for elevating the nozzles to manipulate the screws 36. The movement is accomplished by providing the walls 10 with vertical grooves 42 in which tongues on the ends of the partitioning walls 20` are slidable as indicated at 40. Hangers 44 secured to angle bars 45 on the tops of partitions 20, serve to support the partitions from rods 46 which extend upward through timbers 48 on the top of machine and have hand wheels 50- threaded thereonto. By means' of the wheels 50, the adjustment of the nozzles 18 with respect to the bottoms 15 may be `quickly varied.

In operation, the gates 35 will be adjusted to give that introduction of air which will best aerate the pulp being handled. As the air is projected inward against the inclined portion of the adjacent bottom 15 it rises -alongside the joint 16 and ascends in the column A. This causes the pulp in the column to rise also and thereby sets up circula'- tion in the machine. The froth and pulp pass over the top ofthe partitions 20 as in- Vthe nozzles 18 and bottoms 15 during circulation is thoroughly 'aerated by the air stream being uniformly into the pulp from the nozzles, the rapidity of circulation being sucient to produce fine diffusion of the air bubbles.

lf desired to use -a long cell, the individual nozzle sections of Fig. 5 will be employed, and by varying the adjustments of the gates and the air pressure in the dierent sec-- tions, proper iotation in the successive zones of the cell may be easily maintained, even though the cell be unusually long. the diu- F or the purpose of improving sion of air in the pulp, an air breakin screen 60, Fig. 1, may be horizontally isposed across the ascending column A or the purpose of breaking up large bubbles. The edges of the screen may be conveniently clamped between the adjacent castings.

ln Fig. 6 thereis shown a nozzle and mounting for adjustment of the nozzle 18 independently oi the partition 20. Here the lower end of the partition carries a bracket 65 having ears 66 to cooperate with ears 68 o'n the nozzle and receive a pintle 7 0,. whereby the nozzle is hingedly' connected with the partition. Thus any position of the nozzle with respect to the bottom-and the partition may be had without adjusting the partition. For instance, it the top of the partition has been set to determine a required overflow, the angle of the nozzle or its distance from the bottom may be changed by swingin the same on the hinge. This control is ha lby means of a rod 74: secured to an arm 72 on the nozzle. j

I claim:

1. Pneumatic flotation apparatus compris- 'ing a tank adapted to contain a liquid and having a bottom, a partition'therein spaced from said bottom, and an aerating member on the lower end of said partition.

Y 2. Flotation apparatus comprising a tank adapted to contain a liquid and having a vertical partition therein whose lower end is spaced from the bottom of the tank, and an aerating member on the lower end of the partition and Adirected toward said bottom at an'angle tothe vertical.

3. Flotation apparatus comprising a tank adapted to contain a liquid and having a partition therein dividing said liquid into ascending and descending columns, said tank having an inclined bottom portion, and an aerating member on the lower end of said partition, spaced from said bottom and positioned to direct a stream of air toward said j inclined bottom and at an angle to the vertical. l

a. Flotation apparatus comprising a tank Leonesa,

ing and descending columns and having a bottom, said partition terminating at a point ,spaced from the bottom, and an aerating member on the lower end of said partition having an elongated narrow slot therein for directing a stream of air toward said bottom at an angle to the vertical.

5. Flotation apparatus comprising a tank adapted to contain a liquid having an inclined bottom portion and a partition dividing the liquid into columns, an aerating member mounted on the lower end of said partition and directed toward said bottom portion at an angle to the vertical, said aerating member having an elongated h orizontally disposed slot spaced slightly from said bottom, and means for adjusting said partition to control said spacing.

6. In dotation apparatus a tank adapted to contain pulp, `a partition wall and an elongated aerating member on the lower end thereof having an elongated lslot for directing1 .a thin stream of air into the passing 7. ln flotation apparatus a tank adapted to contain pulp, a partition wall, an elongated aeratingA member mounted on the lower end of saidl wall and provided with an elongated narrow slot for the introduction of air into the pulp in the form of a thin, broad stream, and an adjustable gate olii-said member for varying the size of said s ot.

8. In flotation apparatus a tank adapted to contain pulp, a partition wall, means for bodily adjusting said wall, an aerating member on the lower end of said wall having an elongated narrow slot for the introduction of air into the pulp in the form of a thin layer, and an adjustable member on said aerating member for controlling the size of said slot.

9. In flotation apparatus a tank adapted to contain pulp, a partition wall,.and aerating means mounted on the lower end of said wall, said means comprising a plurality of sections positioned end to end, each section having an elongated narrow slot for the introduction of air in the form of a thin, broad stream into the pulp, and a separate connection for each section with a main air supply.

10. ln flotation apparatus, a tank adapted to containpulp and having an inclined bottom, a partition, an aerating member on the lower end of said partition having an elon gated narrow slot spaced slightly from said ottom for directing a thin, broad stream of air toward said bottom at an angle to the vertical, means to vary the size of said slot, and means to adjust said partition to vary the distancebetween the slot and the bottom, whereby the ribbon of pulp passing between be varied4 as required. v l

ll. In Hotation apparatus, a. tank adapted said aerating member and the bottom' may to contain pulp and having a non-porous. inclined bottom, and an aeratng member` within the tank, spaced from and directed toward said bottom at an angle, the respec- I tive angles of the bottom and the aerating member being such as to insure high velocity of circulation of the pulp under and around 10 the aerating member and upward, and the inclined bottom directing the ioW past the aerating member.

lIn testimony whereof I aflix my signature.

OSCAR JOHNSON. 

